Title:
New observations of the gas cloud G2 in the Galactic Center

Abstract: We present new observations of the recently discovered gas cloud G2 currently
falling towards the massive black hole in the Galactic Center. The new data
confirm that G2 is on a highly elliptical orbit with a predicted pericenter
passage mid 2013. The updated orbit has an even larger eccentricity of 0.966,
an epoch of pericenter two months later than estimated before, and a nominal
minimum distance of 2200 Schwarzschild radii only. The velocity gradient of G2
has developed further to 600 km/s FWHM in summer 2012. We also detect the tail
of similar total flux and on the same orbit as G2 along the trajectory at high
significance. No hydrodynamic effects are detected yet, since the simple model
of a tidally shearing gas cloud still describes the data very well. The flux of
G2 has not changed by more than 10% between 2008 and 2012, disfavoring models
where additional gas from a reservoir is released to the disrupting diffuse gas
component.